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991.
BACKGROUND: Some studies have associated alcohol dependence (AD) with the human serotonin (5-HT)(1B) receptor (HTR1B). This investigation explored the functional responsivity of HTR1B in abstinent AD men using a sumatriptan challenge, while measuring genetic heterogeneity in the HTR1B promoter. METHODS: Abstinent AD men (n = 27) and abstinent men without any alcohol use disorder (n = 19) were administered 6 mg of sumatriptan succinate, subcutaneously. Plasma samples collected over the following 2 hours were assayed for growth hormone (GH) concentrations. His DNA was genotyped for the A-161T and T-261G polymorphisms of the HTR1B promoter and diplotypes determined. RESULTS: Integrated GH responses were predicted by interactions of AD and promoter diplotypes, as well as subject ethnicity. The final model accounted for nearly 35% of the variance in GH responses. Post hoc evaluation revealed that AD was associated with a blunting of GH secretion only among individuals with the most common HTR1B diplotype (TT/TT). CONCLUSIONS: A blunting of GH responses in abstinent AD men was observed only among those with the most common HTR1B promoter diplotype. Less common promoter diplotypes appeared protective. Controlling for genetic background is a useful augmentation of case-control pharmacological challenge strategies designed to elucidate the psychobiology of AD and other complex disorders.  相似文献   
992.
The term keratoameloblastoma has been used to describe a histologically heterogeneous group of ameloblastoma variants which have in common the formation of keratin by the ameloblastomatous epithelium. The English language literature contains reports of only 12 cases of keratoameloblastoma, of which 4 cases exhibited a papilliferous component. We report a unique tumor that we believe falls within the broad histopathologic spectrum of keratoameloblastoma. We review the key clinical and histopathologic features of the previously reported cases of keratoameloblastoma and present an additional case that presented as an expansile, radiolucent lesion with internal opacification between the roots of teeth in the left anterior maxillary alveolar ridge of a 45-year-old white male. There is wide variation in the histopathologic appearance of cases reported under the appellation keratoameloblastoma. Our case exhibited a histopathologic feature shared by only 2 of the previously reported cases, notably islands and anastomosing cords of epithelium forming lamellated, pacinian-like stacks of parakeratin that extruded into the collagenous tumor stroma without eliciting a foreign body response. Due to the small number of reported cases, we are unable to accurately assess whether the biologic behavior of keratoameloblastoma differs from other histologic types of ameloblastoma.  相似文献   
993.
994.
Introduction Obese individuals may have normal insulin–glucose homeostasis, insulin resistance, or diabetes mellitus. Whereas gastric bypass cures insulin resistance and diabetes mellitus, its effects on normal physiology have not been described. We studied insulin resistance and β-cell function for patients undergoing gastric bypass. Methods One hundred thirty-eight patients undergoing gastric bypass had fasting insulin and glucose levels drawn on days 0, 12, 40, 180, and 365. Thirty-one (22%) patients with diabetes mellitus were excluded from this analysis. Homeostatic model of assessment was used to estimate insulin resistance, insulin sensitivity, and β-cell function. Based on this model, patients were categorized as high insulin resistance if their insulin resistance was >2.3. Results Body mass index did not correlate with insulin resistance. Forty-seven (34%) patients were categorized as high insulin resistance. Correction of insulin resistance for this group occurred by 12 days postoperatively. Sixty (43%) patients were categorized as low insulin resistance. They demonstrated an increase of β-cell function by 12 days postoperatively, which returned to baseline by 6 months. At 1 year postoperatively, the low insulin resistance group had significantly higher β-cell function per degree of insulin sensitivity. Conclusions Adipose mass alone cannot explain insulin resistance. Severely obese individuals can be categorized by degree of insulin resistance, and the effect of gastric bypass depends upon this preoperative physiology.  相似文献   
995.
The purpose of this study was to present the long-term follow-up of a case series of arthroscopically assisted fixation of juvenile intraarticular epiphyseal ankle fractures. The functional and radiographic outcomes of 6 patients with a range of follow-up of 1 to 5 years were evaluated. Five of the 6 patients had triplane injuries, whereas the remaining patient sustained a juvenile Tillaux fracture. All of the patients returned to full activity within 14 weeks of surgery, and none of the patients had any restriction in the ankle range of motion at the time of last follow-up. The results of this small series of patients suggest that arthroscopic-assisted, percutaneous fixation of intraarticular juvenile epiphyseal ankle fractures is an effective, less invasive surgical technique. Several surgical maneuvers that are helpful in the consistent execution of this technique are also mentioned.  相似文献   
996.
997.
BACKGROUND: Executive dysfunction has been reported at different ages in autism. It is not clear however, when this impairment emerges or how its expression is affected by development. METHODS: 61 non-mentally retarded autism participants (AUT) and 61 age, gender, and IQ matched typically developing participants (CON) were assessed with two oculomotor executive function tasks, the oculomotor delayed response task (ODR) and the antisaccade task (AS), as well as a visually-guided saccade sensorimotor task (VGS). RESULTS: The AUT group demonstrated impairments in response inhibition and spatial working memory at all ages tested. Developmental improvements in speed of sensorimotor processing and voluntary response inhibition were similar in both groups indicating sparing of some attentional control of behavior. Developmental progression in the speed of initiating a cognitive plan and maintaining information on line over time, however, was impaired in the AUT group indicating abnormal development of working memory. CONCLUSIONS: These results indicate that while executive dysfunction is present throughout development, there is evidence for both typical and atypical developmental progression of executive functions in autism. The plasticity suggested by the developmental improvements may have implications regarding appropriate developmental epochs and types of interventions aimed at enhancing cognitive capacities in individuals with autism.  相似文献   
998.

Objectives:  

To examine the extent to which school climate and school pressure could predict other aspects of adolescents’ lives, most particularly their emotional health and bullying. Furthermore, the study sought to investigate if these relationships were consistent across countries.  相似文献   
999.
BACKGROUND AND PURPOSE: Intimal-medial thickening (IMT) of the carotid wall is an accepted peripheral marker of atherosclerosis. It is associated with increased risk for myocardial infarction and stroke, and lower attention-executive-psychomotor functioning. The purpose of this study was to examine the relationship between IMT and brain activity during a verbal working memory (VWM) task in patients with cardiovascular disease (CVD). METHODS: Thirteen CVD patients underwent functional magnetic resonance imaging (fMRI) during a 2-Back VWM task, and B-mode ultrasound of the carotid arteries. IMT was calculated using an automated algorithm based on a validated edge-detection technique. The relationship between IMT and 2-Back-related brain activity was modeled using partial correlations controlling for age and small vessel disease as measured by white matter signal hyperintensities on MRI (WMH). RESULTS: Higher IMT was associated with lower 2-Back-related signal intensity and in the right middle frontal gyrus, independent of age and WMH. CONCLUSIONS: IMT may be one mechanism contributing to brain dysfunction in CVD. The blood oxygenation level-dependent (BOLD) contrast appears to be highly sensitive to peripheral vascular health as measured by IMT. Future studies should examine the sensitivity and specificity of the BOLD response for predicting cognitive decline in CVD.  相似文献   
1000.
PURPOSE: Hemolysis during extracorporeal membrane oxygenation (ECMO) may be associated with the development of hemoglobinuria (Hb) nephropathy and acute renal failure. For patients requiring ECMO, continuous renal replacement therapy (CRRT) can be simultaneously performed by attaching a hemofilter to the ECMO circuit, thereby shunting part of the ECMO blood flow through the hemofilter. However, the possibility that CRRT may further enhance hemolysis (and the risk of Hb nephropathy) in patients on ECMO has not been previously investigated. METHODS: Medical records of 42 children (1 day-12 years old) who required ECMO (ECMO group, n=25) or ECMO and CRRT (ECMO+CRRT group, n=17) after cardiac surgery were reviewed. RESULTS: Forty-one out of 42 patients had elevated plasma-free hemoglobin (FHb) on the first day of ECMO. For all subjects, peak change (mean+/-SD) in FHb (Peak%C-FHb, 83.6+/-183%) correlated with serum lactic dehydrogenase (150+/-324%, r=0.49, p<0.05) and marginally with ECMO blood flow rate (BFR) (Peak%C-BFR, 36.8+/-51.0%, r=0.29, p=0.06). Compared with the ECMO group, the ECMO+CRRT group had a higher Peak%C-FHb (160+/-259%, p<0.05) and Peak%C-BFR (62+/-64%, p<0.05). Also, there was a significant increase in FHb one day after the initiation of CRRT compared with the level prior to CRRT (73.3+/-49.2 vs. 50.0+/-30.3 mg/dL, respectively, p=0.012). Serum creatinine (but not blood urea nitrogen) was significantly higher in the ECMO+CRRT group compared with the ECMO group. The percent change in serum creatinine during ECMO did not correlate with Peak%C-FHb in the ECMO group. CONCLUSION: Our findings suggest that there is enhanced hemolysis during combined ECMO and CRRT compared with ECMO alone. However, the clinical impact of increased hemolysis on renal function in patients receiving ECMO with or without CRRT remains to be determined.  相似文献   
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